Sertularella areyi Nutting, 1904

Calder, Dale R., 2019, On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA, Zootaxa 4689 (1), pp. 1-141 : 88

Sertularella areyi Nutting, 1904

Fig. 21h

Sertularella areyi Nutting, 1904: 83 , pl. 17, fig. 6.

Type locality. Cuba: near Havana, 100–200 ftm (183–366 m) ( Nutting 1904: 83) .

Material examined. Southwest Florida Shelf, outer shelf west of Sanibel Island, 26°16.67’N, 84°04.08’W, 137 m, 25 July 1981, triangle dredge, one colony fragment, 5 mm high, without gonophores, coll. Continental Shelf Associates, ROMIZ B1978.

Remarks. Hydroids of Sertularella areyi Nutting, 1904 are small (usually less than 1 cm high) but quite striking in colony morphology. Long, slender internodes bear largely exserted and barrel-shaped hydrothecae having 1–3 annular ribs and a thickened hydrothecal rim. It has been reported few times in the western Atlantic, and gonothecae have yet to be described in specimens from the region. Although the type locality is off the north coast of Cuba, in the Gulf of Mexico, the species has been recorded much more frequently in the western Pacific ( Korea, Japan, the Philippines, New Caledonia, Loyalty Islands, Australia, New Zealand), with fertile colonies having been described from there ( Vervoort 1993; Hirohito 1995; Vervoort & Watson 2003). Elsewhere, records of S. areyi exist from Hawaiʻi, surprisingly from the inshore waters of Kâneʻohe Bay and Waikîkî ( Carlton & Eldredge 2009). As well, Vervoort (1993) included S. capensis delicata Millard, 1964 from the east and south coasts of South Africa in the synonymy of the species.

In the western North Atlantic, S. areyi is a species inhabiting waters of the continental shelf and upper slope, having been reported over a depth range between 17– 366 m. Geographically, it is known from offshore waters of South Carolina and Bermuda (Plantagenet Bank) in the north to Cuba ( Nutting, 1904; Wenner et al. 1984; Calder 2000) in the south. The species has also been reported from Brazil ( Oliveira et al. 2016). The only previous record from the Gulf of Mexico is Nutting’s (1904) original account of the species from the north coast of Cuba. This is the first report of the species from the Gulf coast of Florida. Lack of any records of S. areyi from the Caribbean Sea may be due to the paucity of deep-water collecting in the region to date.

Sertularella areyi has been discussed in detail by Vervoort (1993), based on collections from the Philippines, New Caledonia, and the Loyalty Islands. That work includes a detailed synonymy, a description, illustrations, and distribution records of the species. An update was provided by Vervoort & Watson (2003) in a study on hydroids of New Zealand. The extent of genetic divergence between hydroids assigned to S. areyi from the western North Atlantic and those from other oceans is as yet unknown.

Reported distribution. Gulf coast of Florida. First record.

Elsewhere in western North Atlantic. Cuba: near Havana, 100–200 ftm (183–366 m) ( Nutting 1904: 83) .— USA: South Carolina, outer continental shelf, 46–69 m + Georgia, inner (17–22 m), middle (23–29 m) and outer (59–67 m) continental shelf ( Wenner et al. 1984: 21, 40) .— Bermuda: Argus (= Plantagenet ) Bank ( Calder 2000: 1134) .— USA: Florida, outer continental shelf off Sebastian Inlet , 27°52.5’N, 79°57.5’W, 75–98 m ( Calder 2013: 28).

Figures

FIGURE 21. a, Amphisbetia distans: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4387. Scale equals 0.1 mm. b, Amphisbetia distans: gonotheca, Sanibel Island, ROMIZ B4386. Scale equals 0.1 mm. c, Dynamena disticha: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4410. Scale equals 0.1 mm. d, Dynamena pourtalesi: part of hydrocaulus with two hydrothecal pairs, Southwest Florida Shelf, ROMIZ B306. Scale equals 0.2 mm. e, Idiellana pristis: base of hydrocaulus with a branch, Sanibel Island, ROMIZ B4390. Scale equals 0.2 mm. f, Idiellana pristis: part of branch with hydrothecae, Sanibel Island, ROMIZ B4390. Scale equals 0.1 mm. g, Tridentata turbinata: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4393. Scale equals 0.2 mm. h, Sertularella areyi: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B1978. Scale equals 0.2 mm. i, Sertularella diaphana: part of colony with three hydrothecae, Southwest Florida Shelf, ROMIZ B4392. Scale equals 0.2 mm. j, Sertularella unituba: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B2001. Scale equals 0.2 mm.